From 2e7be162996640bbe3b6da694cc064c511b8a5d9 Mon Sep 17 00:00:00 2001 From: Anup Patel Date: Thu, 5 Jun 2025 11:44:47 +0530 Subject: [PATCH] RISC-V: KVM: Don't treat SBI HFENCE calls as NOPs MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The SBI specification clearly states that SBI HFENCE calls should return SBI_ERR_NOT_SUPPORTED when one of the target hart doesn’t support hypervisor extension (aka nested virtualization in-case of KVM RISC-V). Fixes: c7fa3c48de86 ("RISC-V: KVM: Treat SBI HFENCE calls as NOPs") Reviewed-by: Atish Patra Signed-off-by: Anup Patel Link: https://lore.kernel.org/r/20250605061458.196003-3-apatel@ventanamicro.com Signed-off-by: Anup Patel --- arch/riscv/kvm/vcpu_sbi_replace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/riscv/kvm/vcpu_sbi_replace.c b/arch/riscv/kvm/vcpu_sbi_replace.c index 9752d2ffff68..b17fad091bab 100644 --- a/arch/riscv/kvm/vcpu_sbi_replace.c +++ b/arch/riscv/kvm/vcpu_sbi_replace.c @@ -127,9 +127,9 @@ static int kvm_sbi_ext_rfence_handler(struct kvm_vcpu *vcpu, struct kvm_run *run case SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA_ASID: /* * Until nested virtualization is implemented, the - * SBI HFENCE calls should be treated as NOPs + * SBI HFENCE calls should return not supported + * hence fallthrough. */ - break; default: retdata->err_val = SBI_ERR_NOT_SUPPORTED; } -- 2.50.1